隧道岩体赋存地质特征及开挖过程描述

隧道开挖改变了围岩的原始地质环境（如原始地应力场，渗流场，温度场等），为保持围岩的稳定性及工作环境要求，须采取适当的支护与防渗措施。作者从岩土体的赋存地质特征出发，给出了描述隧道开挖过程中力学与水力特征及表征方法。进行了隧道开挖卸荷的有限元模拟计算，讨论了开挖方法对围岩扰动带的影响。研究结果有助于合理地建立隧道开挖问题的流固耦合模型及指导隧道的设计与施工。

Geological Environment of Tunnel Ground and Depiction of the Excavation Process

The primary geological environment(primary ground stress field,seepage field and temperature field,etc)will be changed due to tunnel excavation,in order to keep tunnel ground stable and to protect the work environment,a proper supporting structure and waterproof measure should be taken.Based on the geological environment in which the tunnel is located,a methodology is proposed to depict mechanical and hydraulic behavior in tunnel excavation process.By use of measured data in situ,the deformability and hydraulic properties are studied by numerical analysis methods.The effect of excavation method on the damage zone is discussed.In addition,the influence of stress disturbed boundary is smaller than that of seepage disturbed boundary.Therefore,the seepage boundary condition should be focused on establishing the hydromechanical coupling mathematical models.The conclusions can be as an guide to establish correctly the hydraulicmechanical coupling model.